Chicago Marathon
Race Day Weather
Mild start, strategic wind shifts
Runners will face temperatures starting at 61°F and rising to 66°F, with moderate humidity at 67%. A significant 15 mph headwind will challenge runners from mile 2 and again from miles 9-23, suggesting a conservative approach during these segments. Tailwinds from miles 1 and 4-8, as well as 24-27, offer opportunities to push the pace, but hydration will be essential throughout the race.
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Race Info
The Chicago Marathon starts and finishes in Grant Park, looping through 29 Chicago neighborhoods and crossing the Chicago River six times. The flat, fast course is a Boston qualifier and has produced seven marathon world records, most recently Ruth Chepng'etich's 2:09:56 women's mark in 2024. It's one of the seven Abbott World Marathon Majors, held every year on the second Sunday of October.
